Real-time quantitative RT-PCR is an existing technique for monitoring viral load for HIV, HCV, and other viral infections. However, this test is cost-prohibitive in some resource-limited settings and can require multiple instruments, skilled technicians, and isolated rooms to prevent contamination. The test can thus be inaccessible to patients in some resource-limited settings. Moreover, the efficiency of RT-PCR, the quality of sample and selection of targets, and the methods for interpretation of the data may in some cases present concerns for the accuracy of quantifying RNA using RT-PCR.
Although dipstick-type devices may provide semiquantitative measurements of viral load after amplification in resource limited settings, no quantitative test exists to resolve a 3-fold (i.e., appx. 0.5 log10) change in HIV RNA viral load, which change is considered clinically significant. Accordingly, there is a long-felt need in the art for devices and methods for quantitative measurement, estimates, and/or even detection of viral load or other parameters.